Building structure



Patented Mar. 3, 1942 UNITED STATESl PATENT OFFICE BUILDING STRUCTURE Philip H. Penneil, Belmont Manor, Pa., assignor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania Application July 13, 1939, Serial No. 284,367

7 Claims.

This application is a continuation in part of my copen'ding applications, Serial No. 135,449, led April 7, 1937, and Serial No. 173,326, filed November 8, 1937.

This invention relates to building structures. Specifically it is concerned with floor or Wall coverings made of impregnated fibrous material. Such coverings, consisting essentially of a body made of felted fibers impregnated with asphalt and having a decorative paint coat as the wearing surface, are well known in the trade. They are generally designated as felt base material.

A serious defect of felt base material is that it is not ordinarily feasible to cement the same to a oor or wall. There are many reasons why it is desirable to cement the material into place. So far as walls areI concerned, it is impractical to use materials of this sort unless they can be cemented. So far as oors are concerned, cementing is desirable because it prevents scumng or cracking of the material, curling of its edges, etc. In addition to this, a better oor resultsl if the material is rmly cemented toits base.

Despite the obvious advantages of cementing felt base material into place, the practice has always been avoided because of the diiculties which ensue if it is subsequently attempted to remove the material. It must be recognized as a practical matter that the user of felt base material, in common with the users of other oor coverings such as linoleum, will wish to replace the material even if only at infrequent intervals. Cemented linoleum may be removed from a oor or wall with comparative ease, whether it be cemented directly to the floor or Wall or whether a layer of deadening felt be interposed. In either case the internal strength of the linoleum is greater than the internal strength of the cement or felt, and in consequence the linoleum may be peeled off. When it is peeled, the layer of deadening felt ruptures internally or else the cement itself ruptures. It may be noted that in the case of a linoleum installation embodying a layer of deadening felt, the linoleum offers the greatest resistance to internal rupture and the felt offers the least resistance, the cement lying between the two.

In consequence, the linoleum may be salvaged, but far more important is the fact that the floor or wall from which it has been removed is in such condition that with only a relatively small amount of preparation it is ready to receive another covering.

In the case of felt base materials, an entirely different situation is presented because the impregnated fibrous material is inherently less resistant to rupture than any of the cements heretofore used in the floor or wall covering art. Not only is the material inherently weak, but due to the felting operation it is generally laminar in character and tends to pull apart at different levels between the top and bottom surfaces, depending upon a number of factors such as the manner in which it is pulled from the floor, the uniformity of impregnation, the uniformity of the floor, etc. Therefore, if it is attempted to strip off a piece of cemented felt base material the material itself is destroyed and the floor is left with an ugly and irregular covering of cement and pieces of the asphalt saturated ber. Practically speaking, it is impossible to deal with such a condition satisfactorily. There is no solvent available, within permissible limitations of cost, which could be used to remove the residual felt and cement, and it is a hopeless task to attempt to remove it by mechanical means. Attempts have been made to remove it by the use of blow torches and Scrapers, but these methods have not been satisfactory and are obviously undesirable, particularly for use in homes.

The facts above stated have been well-known for many years and have resulted in a rule of universal application in the industry, that felt base material shall not be cemented in place. Indeed, many manufacturers of this class of goods so treat the back of the material, as, for example, by the application of a wax-like coat, that cement will not adhere to it, thus, so to speak, protecting the user against his own ignorance. (See for example Sumner Patent No. 1,4 42,012.)

The facts just stated have precluded the use of felt base material as a wall covering and have materially diminished the applicability of the material as a floor covering. Such facts have also made it impractical to attain the full life of felt base materials, such as would be obtained if it were feasible to cement them in place.

I have found that these difficulties can be overcome and that felt base material may, by the use of my invention, be cemented to walls or floors and subsequently removed in such a way as to leave the wall or oor in condition to receive another covering and, in most cases, without destruction of the original covering which has been removed. I attain these results by interposing between the material and the wall or oor a strong adhesive coating and adjacent thereto a coating having less resistance to rupture than the felt base material.

Pounds Acaroid resin 664 Alcohol (denatured) 586 #600 BB Slate our 400 I have found that the securing properties of the coating are dependent in a large part upon the amount of filler therein, the maturing time and the temperature to which it is subjected. From my experiments, I have determined certain definite limits of cohesion, within which the required feature of ready removability is obtained. I have found that it is impossible to establish definite formula standards, the effectiveness of which may be completely altered by changes in maturing time and temperature. I have determined that limits of cohesion of 3 to 30 pounds resistance are satisfactory but limits of 6 to 30 pounds are preferred. With greater tensile resistance than 30 pounds, the coating is resistant to a degree to prevent ready removability; with tensile resistance less than 3 pounds, its securing properties are dangerously weak and -the covering may be loosened from the base by severe traffic and excessive wear and for that reason a minimum of 6 pounds is preferred. From my work, it has been found that all felt base products tested have a tensile strength above the range recited-none having ruptured in tests up to 30 pounds. The exact tensile strength of felt base is not accurately determinable by the method employed in testing the limits of cohesion of the coating, however.

The pull test hereafter referred to as the Scott test used to establish these limits may be carried on in the following manner:

'I'o one side of a strip of wood 6" long by 2 wide a thin layer of linoleum cement or paste is applied, using a notched doctor blade to distribute the paste or cement evenly over the entire surface. To the paste or cement is immediately applied a strip of the covering to be tested 8 x 2" wide, one end of which is placed flush with one end of the strip of wood, the other end extending free beyond the wood strip. After rolling to obtain a satisfactory bond between the Wood and the covering, the sample is maintained at normal room temperature for approximately four days to dry the paste or cement. The resistance of the coating to tensile forces is determined by placing the sample in a Scott tensile strength machine at right angles to the direction of the forces to be exerted. The strength of the forces recorded as the covering is removed from the wood strip measures the resistance of the coating to tensile forces.

In place of the coating recited above I may use a coating formulated as follows:

Any desirable Vller composition may be used instead of the above enumerated fillers or any combinations thereof; it is desirable to use formalin since it not only acts as a preservative'but also acts to render the casein water insoluble when the coating is dry; any suitable alkalies may be used in place of borax and sodium metasilicate, for example, caustic soda orl triethanolam The above form a y be varied as desired to compensate for varying manufacturing conditions, provided the nal resistance factor l0 is within the range recited.

Another coating which may be satisfactorily employed may be formulated as follows:

Pounds Acaroid resin 84 Ammonium hydroxide 26 30 Casein (dry) 3 Water 96 With the above formula, the resistance of the coating to tensile forces becomes greater as the amount of casein increases. If a certain amount of casein is not used, the securing properties of the coating are insuicient to prevent the covering being loosened by excessive traffic. Invert su ar in any desired amount mair be added to the a ove composition to provide less resistance if larger amounts of casein are used. As pointed out above, the period of time and the temperature at which the covering is matured also affects the resistance of the coating to tensile forces.

The rupturable coating may be applied prior to application of the paint decoration on the face of the felt base and will then be subjected to the same heat treatment as the `paint decoration, or the coating may be applied after the paint decoration has been matured, in which event, no heating, except that required to dry the coating, will be effected. The formulation of the coating may differ slightly under such conditions in order to attain the desired rupturability, the

time and temperature of maturing, as pointed out, altering the characteristics of the coating.

Preferably, a second coating is applied to the fibrous material, over and concealing the rupturable coating. This coating is applied primarily for decorative purposes and may comprise the customary backing paint which is ordinarily applied to hard surface floor coverings.

While I have described certain preferred coatings, my invention is not restricted thereto since various other coatings may be used, my invention consisting in part in the provision of a structure in which there is a rupturable coating possessing low resistance to tensile forces interposed between the permanent base to which the licor covering is adhesively secured and the partible fibrous stratum, the relative strength of the coating and the partible stratum being such that the coating possesses lower resistance to rupture than the partible stratum and may be readily ruptured to eect removal of the covering material from the base without parting of the partible stratum.

While felt base has been described as a product to which the invention pertains, any of the so-called felt type oor coverings may be employed such, for example, as Linoor which comprises an asphalt saturated felt backing or supporting foundation carrying a layer of linoleum like composition; industrial flooring which comprises a saturated felt base or body carrying a colored asphaltic coating as a. wearing surface; floor coverings in which the base or Ibody may also form the wearing surface, such as floor coverings made in accordance with Jackson Patents Nos. 1,729,832 and 1,729,833 and Finley Patent No, 1,802,009, or any similar floor coverings which luc. bulvxrucl l lona,

COATING R PLASUC include a partible fibrous stratum such as asphalt saturated felt underlayment for resilient tiles and the like.

It is customary in the manufacture of floor coverings of the type which include a saturated felt base or body to apply to the back or under surface of the saturated sheet a coating which is effective for sealing the impregnant against bleeding and incidentally gives the covering a lower surface of pleasing Iappearance for display prior to installation. Many types of seal coatings have been suggested for this purpose. The Patent to Baldwin No. 1,856,370 discloses a felt type covering having a decorative seal coat applied to its lower surface including a resin, such as acroides gum, and a plasticizer for the resin, such as diamyl phthalate. Pohl Patent No. 2,085,602 discloses another type of decorative seal coating for use on asphalt saturated felt base oor coverings, including a silicate solution, rubber latex, pigment and fillers.

Such coatings were specifically designed to provide effective sealing of the base saturant and to form a decorative surface on the covering. No attempt was made to so formulate the coatings, taking into consideration time and temperature conditions and other variable factors which alter the resistance of such coatings to tensile forces and which are encountered in hard surface covering production, that the relative strength of the coating as compared with the tensile strength of the partible brous stratum forming the base or body of the covering would be such that the coating would possess lower resistance to rupture than the partible stratum and could be ruptured to effect removal of the covering from the base to which it was cemented.

I form my building structure in the following manner: First, I prepare the base to receive a covering; that is, it is cleaned and levelled so that it presents a clean, dry, substantially smooth surface. A layer of adhesive is spread evenly over the base; the hard surface covering is laid thereon lbefore the adhesive is dry and rmly pressed thereagainst, as by rolling, placing heavy sand bags thereover, or the like. When the adhesive has dried, the covering is securely attached to the base.

While I have described the rupturable coating as adhering to one side of the partible fibrous stratum, it may be interposed at any place between the covering and the base. For example, it may be spread over the base and permitted to dry thereon before the adhesive is applied thereto.

When it is desired to remove the covering, the

coating may be readily ruptured by exerting tensile forces on the structure. When the covering is removed, the base may be readily put in condition to receive a new covering by washing away the adhesive remaining thereon and yfollowing the process described above. I have found, in many cases, that it is not essential to wash olf the adhesive remaining on the base since a good bond may be secured by merely placing another adhesive coating thereon and securing a covering thereto. Preferably, however, I remove the adhesive, since, in some cases, the adhesive is not spread suiciently smooth to permit a second coating thereover.

In the accompanying drawing illustrating my invention:

Figure 1 is a sectional view of my building structure, showing a hard surface covering secured to a base, a corner of the covering being raised to show the rupturable coating and the press Heteren@ adhesive layer bonding the covering to the base;

Figure 2 is a sectional view similar to Figure 1, showing the coating placed adjacent the base; and

Figure 3 is a sectional view similar to Figures 1 and 2 showing the rupturable coating applied to a partible fibrous covering such as saturated felt underlayment.

Referring to the drawing, there is shown a base 2, a hard surface covering 2 comprising a wearing surface 4, a stratum of partible brous material 5, which is saturated by a waterproofing compound, a rupturable coating 6 and a decorative coating 1, secured to the base 2 by an adhesive layer 8. Figure 2 discloses a modication and shows the base 2 having a hard surface covering 3' secured thereto. The covering consists of a wearing surface 4 which may be of linoleum composition and a stratum of saturated partible fibrous material 5' as, for example, felt saturated with asphalt or the like. In this modication the coating B is placed over the baseit is not carried by the covering-and the adhesive layer 8' bonds the covering thereto. Figure 3 shows 'a similar structure in which the covering 9 is formed of a single sheet of partible fibrous material which may be decorated throughout its extent and saturated with a moisture resistant substance to impart suitable wear resistance or, in the case of underlayments, may be undecorated, but saturated. In this structure a rupturable coating I0 is applied to the covering 9 and no decorative base coating, such as the coatings 1 and 1' of Figures 1 and 2, respectively, is applied, the covering being joined directly to the base I2 by a layer of adhesive I l.

While I have described and illustrated a preferred embodiment of my invention, it will be understood that it is not limited to such form, since it may be otherwise embodied within the scope of the following claims.

I claim:

1. A hard surface covering including a sheet of partible brous material saturated with a moisture-resistant substance and a partible coating secured thereto, the coating being materially weaker than the stratum of brous material in resistance to rupture, whereby if the material is cemented to a base with the coating interposed between the fibrous sheet and the base the coating may be subsequently ruptured to permit stripping of the covering from the base without rupture of the brous material.

2. A hard surface covering including a sheet of partible brous material saturated with a moisture-resistant substance and a partible coating secured thereto, the coating having a resistance to rupture in the range of 3 to 30 pounds as determined by the Scott test and being materially weaker than the stratum of brous material in resistance to rupture, whereby if the material is cemented to a base with the coating interposed between the fibrous sheet and the base the coating may be subsequently ruptured to permit stripping of the covering from the base without rupture of the fibrous material.

3. A hard surface covering including a sheet of partible brous material saturated with a moisture-resistant substance and a partible coating secured thereto, the coating having a resistance to rupture in the range of 6 to 30 pounds as determined by the Scott test and being materially weaker than the stratum of fibrous material in resistance to rupture, whereby if the material is cemented to a base with the coating Examiner interposed between the brous sheet and the base the coating may be subsequently ruptured to permit stripping of the covering from the -base Without rupture of the brous material.

4. A hard surface covering including a sheet of partible fibrous material saturated with a moisture-resistant substance and a partible coating secured thereto, the coating comprising the dried residue of a composition consisting essentially of a modified acaroid resin and a vehicle therefor, the coating being materially weaker than the stratum of iibrous material in its resistance to rupture, whereby if the material is cemented to a base with the coating interposed between the iibrous sheet and the base the coating may be subsequently ruptured to permit stripping of the covering from the base without rupture of the fibrous material.

5. A hard surface covering including a sheet of partible fibrous material saturated with a moisture-resistant substance and a partible coating secured thereto, the coating comprising the dried residue of a coating composition consisting essentially of acaroid resin, casein, and ammonium hydroxide, the coating being materially weaker than the stratum of brous material in its resistance to rupture, whereby if the material is cemented to a base with the coating interposed between the iibrous sheet and the base the coatthe coating interposed between the brous sheet and the base the coating may be subsequently ruptured to permit stripping of the covering from the base without rupture of the brous material.

7. In a building structure, a permanent base, a hard surface covering therefor embodying a stratum of partible fibrous material saturated with a moisture resistant substance, a rupturabie coating and an adhesive layer between the stratum of partible fibrous material and the permanent base, the coating being materially weaker than 'the stratum of iibrous material in resistance to rupture whereby the covering may be stripped from the base without parting of the fibrous stratum.

PHILIP H. PENNELL. 

